Lithium ion battery status and development
The development of electronic technology, high energy to the mobile power demand. Lithium ion battery is a kind of ideal portable power, small volume, light weight, high voltage, discharge is big, etc. Since 1990, the world’s first SONY corporation lithium ion battery, by 2001, the market every year around 4 million such batteries used for pure consumer electronic products. The camcorder laptop computers, mobile phones, etc. More than 95% using lithium-ion secondary battery power.
1, lithium-ion secondary battery principle of work
Used for lithium-ion secondary battery anode materials mainly layered structure LiCoO2, LiNiO2 spinel structure and the structure of these materials LiMn2O4, determines the Li ion can exist in its freedom in ion channel. Various types of carbon materials is currently the most widely used rechargeable lithium ion battery anode materials, they also allow freedom of lithium ion in the meantime the embedded and embedded.
In LiCoO2 system of lithium-ion secondary battery for example is given to illustrate its working principle. Generally, lithium-ion secondary battery consists of positive, electrolyte, diaphragm and negative. When the battery anode, lithium ion from LiCoO2 layer structure, the combining elements of Co + to + Ⅲ increased by approximately 400mah Ⅳ, oxidation reaction, and lithium ion battery electrolyte migrate through the anode carbon anode in the layer structure of materials and carbonization connate into LiCX. When the battery is connected to the load in two electrodes, which occurred on the reaction occurs for charging NiFanYing reaction. The diaphragm is between the positive electrode reaction, the diaphragm can pass through, but not allow ion battery, at the same time, when the electronic through some extent across the micro short circuit, the diaphragm is blocking the protection function.
2, the structure of li-ion rechargeable battery
Current appear on the market lithium-ion secondary battery are divided into two kinds, one kind is square rechargeable lithium ion batteries, a cylinder for lithium-ion secondary battery.
These cells are in cylindrical lithium-ion secondary battery mature manufacturing processes, and on the basis of electronic products in order to adapt to the development trend of light and developed. Cylindrical and square lithium-ion secondary battery components is roughly same, including the general component: positive and negative, the diaphragm, positive, negative and positive lead wire terminals, relief valve, insulation slices, battery shell, etc. Lithium-ion secondary battery structure schematic as shown in figure 2. Lithium-ion secondary battery naming also cylindrical and square two, one of three letters with cylindrical naming and 5 digit, before two letters lithium ion battery (LI), after a letter (R), cylindrical before two numerals with mm in diameter, the maximum for the unit after three figures to 0. LMM for maximum height, such as LIR18650 means for 18mm, high 65mm diameter cylidrical lithium ion battery. After three letters in the square and six numerals, before two letters lithium ion battery (LI), after a letter (S), the former square two numerals with maximum thickness of mm, two numerals with mm for the unit width, hind two Numbers to the maximum height for mm, such as LIS043048 means to 4mm 30mm width, thickness, high 48mm square lithium ion battery.
3, lithium-ion secondary battery status and future development
Japan is the world’s largest producer of lithium ion batteries, also have such batteries patent most populous nation. Lithium electricity industry in China, but later start developing very rapidly, and according to the incomplete statistics, China has roughly 200 scale of production and related lithium ion battery materials company, annual production of billions of lithium ion batteries, insiders expect China will soon surpass Japan to become the world’s production of lithium-ion secondary battery.
Current lithium-ion secondary battery acid lithium cobalt in a positive, negative material is carbon materials, the production process has been quite battery, the battery performance can completely monomer battery to meet the design requirements, and the manufacturing cost also have very good control of lithium-ion secondary battery, the actual production costs are lower than those of the same energy nimh rechargeable batteries (currently the world’s production of nimh batteries are less). But, to make the positive lithium cobalt acid lithium ion batteries, safety performance is poor, especially in some harsh conditions using explosion accidents to. Using lithium manganese acid, phosphoric acid lithium cobalt nickel and iron lithium cobalt materials instead of a new generation of acid lithium battery materials can be a very good solution to the safety performance, also can further reduce production cost, this technology is expected in the lithium ion battery power to get a promotion.
